Atypical ecology of Pantala flavescens (Fabr.) on Easter Island (Anisoptera: Libellulidae)

摘要: P. flavescens on Easter Island exhibits peculiar life history adaptations not documented from populations elsewhere. Adults seem to have abandoned the long-distance dispersal behaviour for which this circumtropical dragonfly species is notorious. They are relatively poor flyers, show a tendency aggregate and forage in windsheltered areas, display perching reflex at sudden windrises. — The sp. reproduces major crater lakes, as well several smaller ponds that occur scattered around island. In young larvae preyed upon by introduced Gambusia fish. Medium fullgrown escape predation (through protection provided abdominal spines?), but subject chronic starvation because of overall scarcity suitable prey. Selection non-migrating may explain flavescens. Poor larval nutrition considered been key epigenetic initiating factor.